Abstract: A method to enable unique identification of serial devices having a common bus for communication with a bus master includes the step of serially clocking a mask value through a plurality of serial devices until each serial device stores a corresponding portion of the mask value. Each serial device responds to a subsequent command only if enabled by the corresponding portion of the mask value. Another method includes the step of initializing a plurality of serial devices to one of a first mode and a second mode. If the plurality of devices are in the second mode, a mask value is serially clocked through the plurality of serial devices until each serial device stores a corresponding portion of the mask value. When in the first mode every serial device responds to a subsequent command. When in the second mode, only serial devices enabled by the corresponding portion of the mask value respond to the command. An apparatus includes a plurality of serial devices coupled to a bus master by a bus.

Abstract: An apparatus for interfacing an integrated circuit with external circuitry includes a transistor having an emitter coupled to a node for receiving a control current (IP) from the integrated circuit. A beta compensator disposed within the integrated circuit provides a compensating current (IM) to the node. The compensating current IM is proportional to a base current (IB) of the transistor. A method of interfacing the integrated circuit with external circuitry includes the step of providing the control current (IP) from the integrated circuit to a node coupled to a transistor emitter. A compensating current (IM) is provided to the node in response to the transistor base current (IB). The net node current provided to the emitter is IP+IB so that the transistor collector current is substantially the same as the control current. The transistor collector is coupled to the external circuitry.

Abstract: A portable waste disposal apparatus includes a stand for receiving a portable bowl and a waste container. The portable bowl includes a receiving port and a disposal port. A disposal port cover permits waste to pass when the cover is in an open position. Waste is prevented from passing through the disposal port when the cover is in a closed position. Actuation of the disposal port cover is independent of pressure within the portable bowl (e.g., due to waste, water, or purging fluid). In various embodiments, the cover slides or pivots between the open and closed positions. A method of disposing of waste includes the step of receiving waste into the portable bowl through the receiving port. The portable bowl is positioned to receive toilet purging fluid through the receiving port when placed within a toilet. The toilet is flushed to discharge the received purging fluid and waste through the disposal port of the portable bowl.

Abstract: A method of tuning a DCXO includes the step of providing a coarse tuning array and a fine tuning array of capacitors fabricated on the same integrated circuit die. The coarse array is adjusted until the difference between a desired frequency and the output frequency corresponds to a change in capacitance no greater than half the range of the fine tuning array. In one embodiment, the fine tuning array is adjusted to mid-range before adjusting the coarse tuning array. A DCXO apparatus includes at least one integrated circuit segmented switched capacitor network providing a capacitance that is a nonmonotonic function of a composite input code. The segmented switched capacitor network includes parallel coupled binary weighted and thermometer coded switched capacitor networks for coarse and fine tuning, respectively.

Abstract: A common mode feedback circuit includes first and second nodes defining a differential node pair. A collective plurality of transconductors includes a first plurality of transconductors associated with the first node and a second plurality of transconductors associated with the second node. Each plurality, for example, may consist of 2 transconductors such that one may be serve as a common mode current sink and the other may be operated as a current source during calibration. At least one transconductor of the collective plurality has an adjustable transconductance. In various embodiments, each node has at least one transconductor with an adjustable transconductance. The common mode feedback circuit includes a calibration engine. The calibration engine adjusts at least one adjustable transconductor until a sensed differential voltage across the differential node pair is substantially zero without the use of external current sources.

Abstract: A method for coupling a wheelchair to an exercise device includes the step of receiving a first wheel of the wheelchair in a first wheel stop to limit forward motion relative to the exercise device. A pin is inserted through the wheel stop and behind the inner periphery of the wheel to limit backward motion of the wheelchair. If necessary, a leg of the exercise device is longitudinally adjusted to adjust a distance between components of the exercise device and the user. A second wheel may be similarly pinned to limit both translation and rotation of the wheelchair relative to the exercise device. The user may then perform the desired exercise routines. Upon completion, the user can disengage from the exercise device by removing the pins.

Abstract: A pump includes an impeller, a stator, and a plurality of permanent magnets forming bearing poles coupled to a selected one of the stator or the impeller. The pump further includes a plurality of shorted coils coupled to the other of the stator and the impeller. The plurality of bearing poles and shorted coils co-operate to form an electrodynamic bearing during rotation of the impeller. The electrodynamic bearing supports the impeller either axially or radially during operation of the pump. Currents induced into each coil by a single bearing pole or by a plurality of bearing poles substantially simultaneously produce an electrodynamically generated magnetic field that repels the inducing bearing pole(s) when the impeller is rotating.

Abstract: A digital-to-analog conversion circuit includes first and second DACs. Switch circuitry couples a selected output of only one of the DACs to an output node at any given time. In one embodiment, a second output of the first DAC is coupled to the first output of the second DAC at a common node. The first output of the first DAC is coupled to a first switch node and a second output of the second DAC is coupled to a second switch node. A first switch couples the common node to the first switch node in response to a first switch signal. A second switch couples the common node to the second switch node in response to a second switch signal. The switch signals ensure that the common node is coupled through the first and second switches to only one of the first and second switch nodes at any given time.

Abstract: A subscriber loop interface circuit having bifurcated common mode control loops includes a DC common mode control for controlling tip and ring DC common mode characteristics, and an AC common mode control for controlling tip and ring AC common mode characteristics, wherein the AC and DC common mode controls are independent. In one embodiment, the DC common mode control includes a tip current source for generating a tip current, idt, and a ring current source for generating a ring current, idr, Each of idt and idr is proportional to a difference between a DC tip voltage (TIPDC) and a control voltage (Vcmcontrol). Thus, in one embodiment, idt=gdt(TIPDC−Vcmcontrol), and idr=gdr(TIPDC−Vcmcontrol). In one embodiment, the AC common mode control includes a tip current source for generating a tip current, iat, and a ring current source for generating a ring current, iar. Each of iat and iar is a function of an AC tip voltage (TIPAC) and an AC ring voltage (RINGAC).

Abstract: Methods for servicing queued requests include the step of queueing at least one request for an initial wait time until at least one agent is available for accepting the queued request. A delay element is provided so that assignment of the queued request is delayed for a delay time. The queued request is then assigned to an available agent. In one embodiment, the delay time is a pre-determined availability pendency time independent of the initial wait time. In another embodiment the request is delayed until a pre-determined queue time has elapsed. In another embodiment, the request may be delayed up to a pre-determined availability pendency time as long as a pre-determined queue time is not exceeded. The delay element need not change the queue discipline. Various queue disciplines including first-in-first-out (FIFO), group FIFO, and modified group FIFO are described for a queueing mechanism incorporating a delay element.

Abstract: Methods and apparatus for enabling collaboration with web pages and other resources is described. A method includes the step of establishing a collaboration session between a first client and a second client. A requested resource is cached with the session host in response to a request having a first uniform resource locator (URL) issued by the first client, if the requested resource is a pre-determined type of resource. A second URL is provided to the second client. The second URL identifies the requested resource or the cached resource in accordance with whether the requested resource is cached. Apparatus for enabling collaboration includes a web server, a cache, and a filter. The web server provides a requested web page in response to a first client's request. The filter stores the requested web page in the cache, if the requested web page is a pre-determined type of web page. A number of pre-determined characteristics for caching are described in various embodiments of the methods and apparatus.

Abstract: Methods and apparatus for enabling collaboration between clients with respect to dynamic resources are described. The method includes the step of establishing a collaboration session between a first client and a second client through a session host. A first client request having a first uniform resource locator (URL) identifying a host other than the session host is re-directed through the session host. In one embodiment, the retrieved resource is modified such that for each embedded request identifying a host other than the session host, its associated embedded URL is replaced with a re-directed URL incorporating the embedded URL. The re-directed URL re-directs the corresponding request for a resource identified by the embedded URL through the session host. In an alternative embodiment, the retrieved resource is not modified. In either embodiment, the resulting resource is cached if necessary (e.g., when the resource is dynamic).